Rolling mill



L. IVERSEN ROLLING MILL May 31, 1938.

Filed Aug. 26, 1956 3 Sheets-Sheet l J v I LL 'r fh lNVENTOR 5W 316w? fiat/M May 1 I9 3. L. IVERSEN 2,1193% ROLLING- MILL Filed Aug. 26, 1936 3 Sheets-Sheet 2 INVENTOR Za/W" L. IVERS E N ROLLING MILL s Sheets-Sheet 3 FiIed Aug'. 26, 1936 Patented May 31, 19 38 ROLLING MILL Lorenz Iversen, Pittsburgh, Pa., assignor to Mesta Machine Company, Pittsburgh, Pa., a corporation of Pennsylvania Application August 26, 1936, Serial No. 97,921

' 10 Claims.

This invention relates to -rolling mills and is herein particularly described as applied to a cold rolling mill for the skin passing of annealed sheets or strips, although the invention has numeroua other applications.

In the present practice of cold strip manufacture the starting material, which is hot rolled strip, is reduced substantially to the desired gauge by a series of cold passes without intermediate annealing. It is customary to give the material a final anneal in order to soften it after the reducing operation. It is also customary to give the metal a "skin pass after this anneal. The skin pass imparts the desired temper to the steel, flattens it, equalizes the gauge, and improves its surface. The amount of reduction taken in skin passing is extremely small, only a few percent at the most, but the conditions are such that enormous pressures are required. This is particularly so if the skin passing is effected without. the use of tension. The pressures are so high that the screw-down mechanism is usually loaded to capacity, and oftentimes the frictionin the screws is so great that difiiculty is encountered in 25 moving them either to relieve the screw pressure or to get a minute adjustment for the purpose of getting accurate gauge. It is desirable to apply pressure independently of the screw for by so doing the difiiculties above mentioned can be overcome. However, it is also highly desirable that the screw exert its pressure through positive mechanical means rather than through some fluid medium. The reasons for this can be better understood after the structure of my present invention has been described, and they are discussed in detail below.

According to'the present/invention I employ in combination with a rolling mill having screwdown mechanism engaging the chock blocks of the roll, fluid means for supplementing the screw pressure and controllable independently thereof.. I prefer to employ a number of fluid cylinders symmetrically arranged about the 45 screw. These cylinders may readily be'formed in the chock block structure and their plungers are arranged against the top of the window in the housing or against an interposed pressuretransmitting member.

In the accompanying drawings illustrating present preferred embodiments of the invention, Figure 1 is a side elevation largely in diagram showing the invention as applied to a skin passing mill of the 4-high type;

Figure 2 is a view to enlarged scale showing a.

part of the housing, the chock block and the pressure-applying means; v

Figure 3 is a similar view showing a modification; Q

Figure 4 is a horizontal section taken on the line IV-IV of Figure 3;

Figure 5 is a vertical section on the line VV of Figure 4; and

Figure 6 is a vertical section on the line VI--VI thereof.

Referring first to Figure '1, there is shown a rolling mill having housing 2 with windows 3 therein to accommodate the chock blocks for the rolls. The mill has working rolls 4 and backin rolls 5. The necks 6 of the bottom backing roll are mounted in chock blocks 1 at the bottom of the windows 3. The necks 8 of the upper backing roll are mounted in chock blocks 9 which are vertically adjustablein the windows 3 so as to obtain the desired setting of the rolls. The customary drive and roll balance mechanisms are employed, but these are omitted from the drawings for the sake of clearness in illustration. The chock f blocks*for the working rolls 4 are omitted for the same reason.

The vertical position of the chock block 9 is primarily determined by a screw l0 driven through customary gearing by a screw-down motor II controlled by the operator through a controller I An indicating diall3 shows the setting of the rolls.

'The screw Ill has a rockable bearing on the chock block, being provided with a spherical bottom bearing on a correspondingly shaped seat M in the top of the chock block 9. The screw thus has positive mechanical engagement for the chock block for exerting pressure thereon, and except for theminutedifferences represented by elastic deformation of the parts, the dial 13 gives an accurate reading of the screw-down setting. It is desired to augment the pressure obtainable by the screw-down mechanism and this is accomplished by hydraulic plungers I 5 mounted in cylinders which are formed in the top of the chock block structure and are connected through a pipe I1 to a source of pressure. In Figure 1 the pipe I1 is shown connected through a control valve l8 to an accumulator l9 supplied by a pump 20. By this mechanism the amount of pressure in the system can be accurately controlled and the pressure can be removed entirely if that is desired. A second pipe Ila may also be employed as more fully set out below.

Figures 3 to 6, which show a modified construction, illustrate the connections in detail. The

-modiflcation of these figures over the showing of Figure 2 consists simply in the fact that instead of the plungers bearing directly against the housing they bear against a pressure-transmitting ring 2| which lies in the top of the window 3 and is held in place by bolts 22. Except for this 'feature the mechanism illustrated in Figures 3 to 6 is to all intents and purposes the same as that illustrated in Figure 2, and one description will suflice.

The cylinders may be formed in an integral extension of the chock block 9 but for simplicity in manufacture they are preferably formed in a body 23 having a central opening 24 therein (Figure 6) arranged to accommodate the screw l0 and to fit against a shoulder 25 which holds the body in position. In the forms of the, invention illustrated there are four cylinders arranged symmetrically around thescrew I 0 (Figure 4). These cylinders are lettered respectively lGa, l6b,

I60, and "id. The pipe I! leads directly into the cylinder I61: and the pipe I la leads into the cylinder IGb. Cylinders 16a and I60, which are diametrically opposite one another and considered alone are symmetrically disposed around the screw, are connected together, and the cylinders lGb and lBd, which have a like relationship, are likewise connected together. This arrangement permits the using all four cylinders or only two of them by suitable manipulation of the control valves l8 and l8a. The connection between the cylinders |6a and H50 is by means of horizontal bores 26 and 21 in the body 22. These bores intersect at 28 and are connected to their respective cylinders by vertical bores 29. Their ends are closed by threaded plugs 30.

It will be seen that when the system is filled with liquid pressure which is communicated from the accumulator is to the cylinder I So, upon the opening of the valve l8 it will be likewise immediately communicated to the cylinder lie. The cylinders 3b and "id are similarly connected.

The valves l8 and Ma are of usual construction and serve not only to connect the cylinders to the source of pressure but also to connect the cylinders to the'atmosphere for the purpose of relieving the pressure.

Each of the plungers I5 is provided with a packing 3| and a bleed 32 closed by a screw plug 33. This arrangement permits of venting air from the system when it is installed and to insure that all of the cylinders and passages will be filled with liquid. A supplemental packing 34 is employed at the top of each cylinder. Despite the use of these packings and with the utmost of care in manufacture; a certain amount of leakage around the cylinders may still be expected at the very high pressures employed (I contemplate, for example, applying sufllcient pressure to exert a force of one million pounds or more) and this escaped water, although small in amount, is most undesirable, particularly in skin passing, because the sheets or strips are bright and polished andmust not become spotted or rusted. I therefore provide a collecting trough 35 around the block 22. This trough may be connected to a suitable drain pipe, not shown.

My invention has numerous advantages. It is applicable to existing mills and because the pres- "sure from the cylinders is obtained independently of movement of the screw, the pressure on the screw can be largely or entirely relieved when desired so that screw adjustments can be most 'cylinder under the screw itself.

easily and accurately made. The arrangement does not involve any multiplication of the screw trayel, as would be the case if there were interconnected with the fluid cylinders another Such an arrangement would require a considerable enlargement of the normal screw travel and because of inevitable leakage it could not be satisfactorily and permanently calibrated as is done by the dial l3 in the mechanism above described. The pressure to be applied can be made just as great as desired by adjusting the loading on the accumulator l9, and if for certain purposes it is unnecessary to use the cylinders the screwdown mechanism can be operated in the ordinary way. The device is not dependent for success upon maintaining a definite liquid content, any leakage which might occur being immediately made up from the supply source.

I have illustrated and described certain preferred embodiments of the invention. It will be understood, however, that these are by way of illustration only and that the invention may be otherwise embodied within the scope of the following claims.

I claim:

1. In a rolling mill, 9. pair of rolls, a housing, a chock block for one of the rolls adjustably carried by the housing, an adjusting screw, power means for rotating the screw and thus applying pressure to the chock block, and fluid means for supplementing the screw pressure, the fluid pressure being controllable independently of the screw pressure.

2. In a rolling mill, a pair of rolls, a housing, a chock block for one of the rolls adjustably carried by the housing, an adjusting screw, power means for rotating the screw and thus applying pressure to the chock block, fluid actuated means for supplementing the screw pressure, a source 'of fluid imder pressure, and a controlled connection between the source and the pressure means.

3. In a rolling mill, a pair of rolls, a. housing, a chock block for one of the rolls adjustably carried by the housing, an adjusting screw, power means for rotating the screw and thus applying pressure to the chock block, fluid actuated means for supplementing the screw pressure, a source of fluid under pressure, a connection between the source and the pressure means, and means for controlling the fluid pressure independently of the'screw pressure.

4. In a rolling mill, a pair of rolls, a housing, a chock block for one of the rolls adjustably carried by the housing, an adjusting screw for applying pressure to the chock block, the screw having a positive mechanical engagement with the block for exerting pressure thereon, a fluid cylinder interposed between the housing and the block and so positioned as to exert pressure on the block in the same general direction as the screw exerts pressure thereon, and means for supplying fluid under pressure to the cylinder.

5. In a rolling mill, a pair of rolls, a housing, a chock block for one of the rolls adjustably carried by the housing, an adjusting screw for applying pressure to the chock block, the screw having a positive mechanical engagement with the block for exerting pressure thereon, a plurality of fiuid cylinders interposed between the housing and the block and symmetrically disposed around the screw and so positioned as to exert pressure on the block in the same general direction as the screw exerts pressure thereon, and

chock block for one of the rolls adjustabiy carmeans for supplying fluld under pressure to the cylinders.

6. In a rolling mill, 9. pair of rolls, a housing, a chock block for one of the rolls adjustably carried by the housing, an adjusting screw for applying pressure to the chock block, the screw having a positive mechanical engagement with the block for exerting pressure thereon, a plurality of fluid cylinders interposed between the housing and the block and so positioned as to exert pressure on the block in the same general direction as the screw exerts pressure thereon,

means for supplying fluid under pressure to the cylinders, and connecting ports between the cylinders.

7. In a rolling mill, a pair of rolls, a housing, a chock block for one of the rolls adjustably carried by the housing, an adjusting screw for applying pressure to the chock block, the screw having a positive mechanical engagement with the block for exerting pressure thereon, a plurality of fluid cylinders arranged in sets and interposed between the housing and the block and so positioned as to exert pressure on the block in the same general direction as the screw exerts pressure thereon, and means for separately supplying fluid under pressure to the several sets of fluid cylinders.

8. In a rolling mill, a 'pair of rolls, a housing, a

ried by the housing, an adjusting screw for posi tioning the chock block, the screw having a positive mechanical engagement with the block for exerting pressure thereon, means for indicating the setting of the screw, a fluid cylinder interposed between the housing and the block and so positioned as to exert-pressure on the block in the same general direction as the screw exerts pressure thereomand means "for supplying fluid under pressure to the cylinder.

9. In a rolling mill, a pair of rolls, a housing, a chock block for one of the rolls adjustably carried by the housing, a plurality of fluid cylinders interposed between the housing and the block and efiective for applying pressure to the block, means for supplying fluid under pressure to the several sets of cylinders, and means for independently regulating the fluid supply to different sets of cylinders.

10. In a rolling mill, a pair of rolls, a housing, a chock block for one of the rolls adjustably carried by the housing, a plurality of fluid cylinders interposed between the housing and the block and effective for applying pressure to the block means for supplying fluid under pressure to the several cylinders, and means for independently regulating the fluid supply to different cylinders.

LORENZ IVERSEN. 

